-LRB- CNN -RRB- -- A convicted child pornographer in Pennsylvania was sentenced Tuesday to 12 years in federal prison , thanks in part to three girls featured in CNN 's Freedom Project who provided information to U.S. authorities .

Jeffrey Herschell , 54 , of Washington , Pennsylvania , visited an Internet site that showed live sex shows that forced young girls in the Philippines to act out customers ' fantasies , U.S. investigators said .

`` Whatever the American client wants us to do , we must do it , '' `` Gen '' told CNN in May 2011 for the documentary `` The Fighters . '' `` Gen '' and her friends were schoolmates and just 8 years old when the abuse occurred .

An investigator from Homeland Security Investigations , part of U.S. Immigration and Customs Enforcement , told CNN the information the three girls provided him was integral to the case against Herschell .

Their information launched an investigation that uncovered a ring operating live-streaming shows of children engaging in sexually explicit conduct . Customers from around the globe , including an estimated 10 to 15 from the United States , paid to view the shows and direct them , in some cases .

When HSI agents executed a search warrant on Herschell 's home in 2011 , they found computers , cell phones and hard drives containing dozens of explicit videos and images of children .

The inquiry involved several U.S. agencies , the Philippines national police and the non-profit group Visayan Forum Foundation , which fights modern-day slavery .

READ MORE : Victims endure lives degraded by traffickers

@highlight

A Pennsylvania man gets 12 years in federal prison for child pornography

@highlight

He accessed live sex shows of girls in the Philippines on the Internet , investigators say

@highlight

Information from girls in a CNN Freedom Project documentary led to his arrest